Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/spark/SparkConf at StreamingT$.main(StreamingT.scala:8) at StreamingT.main(StreamingT.scala) Caused by: java.lang.ClassNotFoundException: org.apache.spark.SparkConf at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ... 2 more
原因
NoClassDefFoundError表示在运行时找不到类
<!--运行依赖-->
<dependencies>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-core_2.11</artifactId>
<version>2.3.0</version>
<scope>provided</scope>
</dependency>
</dependencies>
<scope>provided</scope>导致在编译时忽略了这个依赖! 把这行注释掉即可!如果打包时不需要将这个依赖打进去 , 则需要开启!
测试
<!--运行依赖-->
<dependencies>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-core_2.11</artifactId>
<version>2.3.0</version>
<!--<scope>provided</scope>-->
</dependency>
</dependencies>
原文：https://www.cnblogs.com/wyh-study/p/12353955.html